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Energy Efficiency in Water and Wastewater Facilities
A Guide to Developing and Implementing Greenhouse Gas Reduction Programs

Energy Efficiency


EPA’s Local Government Climate and Energy
Strategy Series
The Local Government Climate and Energy Strategy Series provides a comprehensive, straightforward overview of greenhouse gas (GHG) emissions reduction strategies for local governments. Topics include energy efficiency, transportation, community planning and design, solid waste and materials management, and renewable energy. City, county, territorial, tribal, and regional government staff, and elected officials can use these guides to plan, implement, and evaluate their climate change mitigation and energy projects.
Each guide provides an overview of project benefits, policy mechanisms, investments, key stakeholders, and other implementation considerations. Examples and case studies highlighting achievable results from programs implemented in communities across the United States are incorporated throughout the guides.
While each guide stands on its own, the entire series contains many interrelated strategies that can be combined to create comprehensive, cost-effective programs that generate multiple benefits. For example, efforts to improve energy efficiency can be combined with transportation and community planning programs to reduce GHG emissions, decrease energy and transportation costs, improve air quality and public health, and enhance quality of life.

All documents are available at: www.epa.gov/statelocalclimate/resources/strategy-guides.html.

ENERGY EFFICIENCY ■■Energy Efficiency in Local Government Operations ■■Energy Efficiency in K–12 Schools ■■Energy Efficiency in Affordable Housing ■■Energy-Efficient Product Procurement ■■Combined Heat and Power ■■Energy Efficiency in Water and Wastewater Facilities
TRANSPORTATION ■■Transportation Control Measures

SOLID WASTE AND MATERIALS MANAGEMENT ■■Resource Conservation and Recovery
RENEWABLE ENERGY ■■Green Power Procurement ■■On-Site Renewable Energy Generation ■■Landfill Gas Energy

Please note: All Web addresses in this document were working as of the time of publication, but links may break over time as sites are reorganized and content is moved.

Executive Summary_________________________________________________________________v 1. Overview _________________________________________________________________________1 2. Benefits of Improving Energy Efficiency in Water and Wastewater Facilities _____3 3. Planning and Implementation Approaches ______________________________________6 4. Key Participants ________________________________________________________________ 16 5. Foundations for Program Development ________________________________________ 20 6. Strategies for Effective Program Implementation ______________________________ 21
Strategies for Developing an Energy Efficiency Program __________________________________ 22 Strategies for Engaging the Community _______________________________________________ 23
7. Investment and Financing Opportunities ______________________________________ 24
Investment _______________________________________________________________________ 24 Financing ________________________________________________________________________ 25
Financial Vehicles ______________________________________________________________ 25 Funding Sources _______________________________________________________________ 26
8. Federal, State, and Other Program Resources __________________________________ 28
Federal Programs __________________________________________________________________ 28 State Programs ____________________________________________________________________ 29 Other Programs ___________________________________________________________________ 30
9. Case Studies____________________________________________________________________ 32
City of O’Fallon, Missouri ___________________________________________________________ 32 Program Initiation ______________________________________________________________ 32 Program Features_______________________________________________________________ 32 Program Results ________________________________________________________________ 33
Greater Lawrence Sanitary District, North Andover, Massachusetts _________________________ 33 Program Initiation ______________________________________________________________ 33 Program Features_______________________________________________________________ 34 Program Results ________________________________________________________________ 35
10. Additional Examples and Information Resources _____________________________ 36 11. References ____________________________________________________________________ 45

Developing and Implementing Energy Efficiency Programs
Saving energy through energy efficiency improvements can cost less than generating, transmitting, and distributing energy from power plants, and provides multiple economic and environmental benefits. Energy savings can reduce operating costs for local governments, freeing up resources for additional investments in energy efficiency and other priorities. Energy efficiency can also help reduce air pollution and GHG emissions, improve energy security and independence, and create jobs.
Local governments can promote energy efficiency in their jurisdictions by improving the efficiency of municipal facilities and operations and encouraging energy efficiency improvements in their residential, commercial, and industrial sectors. The energy efficiency guides in this series describe the process of developing and implementing strategies, using real-world examples, for improving energy efficiency in local government operations (see the guides on local government operations, energy efficiency in K–12 schools, energy-efficient product procurement, and combined heat and power) as well as in the community.
Energy Efficiency in Water and Wastewater Facilities
This guide describes how water and wastewater facilities can lead by example and achieve multiple benefits by improving the energy efficiency of their new, existing, and renovated buildings and their dayto-day operations. It is designed to be used by facility managers, energy and environment staff, local government officials, and mayors and city councils.
Readers of the guide should come away with an understanding of options to improve the energy efficiency of water and wastewater facilities. Readers should also understand the steps and considerations involved in developing and implementing these energy efficiency improvements, as well as an awareness of expected investment and funding opportunities.

■■Energy Efficiency: Energy Efficiency in Local Government Operations Local governments can implement energy-saving measures in existing local government facilities, new and green buildings, and day-to-day operations. Efforts to improve energy efficiency in water and wastewater facilities can be combined with other energy-saving measures to create a comprehensive municipal energy efficiency strategy.
■■Community Planning and Design: Smart Growth Smart Growth involves encouraging development that serves the economy, the community, and the environment. A community that adopts smart growth principles may develop policies that optimize the siting of water and wastewater treatment systems to reduce the energy needed to pump water to and from members of the community.
■■Energy Efficiency: Combined Heat and Power Combined heat and power (CHP), also known as cogeneration, refers to the simultaneous production of electricity and thermal energy from a single fuel source. Wastewater facilities can install anaerobic digesters that generate methane, which can be burned in a CHP system on site to heat and power the facility.
■■Renewable Energy: Landfill Gas Energy Landfill gas energy technologies capture methane from landfills to prevent it from being emitted to the atmosphere, reducing landfill methane emissions by 60–90%. The process of landfill gas recovery and use is similar to that of recovering methane from anaerobic digesters, and could be applied to water and wastewater treatment facilities situated near landfills.
■■Renewable Energy: On-Site Renewable Energy Generation Local governments can implement on-site renewable energy generation by installing wind turbines, solar panels, and other renewable energy generating technologies. Water and wastewater facilities with adequate land or roof area could install on-site renewable energy generators, complementing their efforts to reduce GHG emissions through energy efficiency.

Energy Efficiency in Water and Wastewater Facilities | Local Government Climate and Energy Strategy Series

Executive Summary


The guide describes the benefits of energy efficiency in water and wastewater facilities (Section 2); a step-bystep approach to improving energy efficiency in new and existing water and wastewater facilities (Section 3); key participants and their roles (Section 4); the policy mechanisms that facilities have used to support energy efficiency programs in their operations (Section 5); implementation strategies for effective programs (Section 6); investment and financing opportunities (Section 7); federal, state, and other programs that may be able to help water and wastewater facilities with information or financial and technical assistance (Section 8); and finally two case studies of water or wastewater facilities that have successfully improved energy efficiency in their operations (Section 9). Additional examples of successful implementation are provided throughout the guide.
Relationships to Other Guides in the Series
Local governments can use other guides in this series to develop robust climate and energy programs that incorporate complementary strategies. For example, local governments can combine efforts to improve energy efficiency in water and wastewater facilities with energy efficiency in local government operations, smart growth strategies, combined heat and power systems, landfill gas energy, and on-site renewable energy generation to help achieve additional economic, environmental, and social benefits.
See the box on page v for more information about these complementary strategies. Additional connections to related strategies are highlighted in the guide.


Executive Summary

Energy Efficiency in Water and Wastewater Facilities | Local Government Climate and Energy Strategy Series

Energy Efficiency in Water and Wastewater Facilities
Energy use can account for as much as 10 percent of a local government’s annual operating budget (U.S. DOE, 2005a). A significant amount of this municipal energy use occurs at water and wastewater treatment facilities. With pumps, motors, and other equipment operating 24 hours a day, seven days a week, water and wastewater facilities can be among the largest consumers of energy in a community—and thus among the largest contributors to the community’s total GHG emissions. Nationally, the energy used by water and wastewater utilities accounts for 35 percent of typical U.S. municipal energy budgets (NYSERDA, 2008). Electricity use accounts for 25–40 percent of the operating budgets for wastewater utilities and approximately 80 percent of drinking water processing and distribution costs (NYSERDA, 2008). Drinking water and wastewater systems account for approximately 3–4 percent of energy use in the United States, resulting in the emissions of more than 45 million tons of GHGs annually (U.S. EPA, 2012b).
Water and wastewater utilities can also reduce energy use by promoting the efficient use of water, which reduces the amount of energy needed to treat and distribute water. In California, for example, urban water use accounts for 70% of the electricity associated with water supply and treatment (Elkind, 2011). Water use efficiency can also help avoid the need to develop new water supplies and infrastructure. This guide provides some information on approaches to improve water use efficiency (such as installing low-flow plumbing fixtures), but concentrates primarily on direct energy efficiency improvements in facilities.
More information on water use efficiency for water and wastewater utilities is available from:
• EPA’s Water Efficiency Strategies page: http://water. epa.gov/infrastructure/sustain/wec_wp.cfm
• EPA’s WaterSense site: http://epa.gov/watersense/ pubs/utilities.html

These economic and environmental costs can be reduced by improving the energy efficiency of water and wastewater facilities’ equipment and operations, by promoting the efficient use of water (see text box on this page), and by capturing the energy in wastewater to generate electricity and heat. Improvements in energy efficiency allow the same work to be done with less energy; improvements in water use efficiency reduce demand for water, which in turn reduces the amount of energy required to treat and distribute water. Capturing the energy in wastewater by burning biogas from anaerobic digesters in a combined heat and power system allows wastewater facilities to produce some or all of their own electricity and space heating, turning them into “net zero” consumers of energy.
Local governments can also reduce energy use at water and wastewater facilities through measures such as water conservation, water loss prevention, stormwater reduction, and sewer system repairs to prevent groundwater infiltration. Measures to reduce water consumption, water loss, and wastewater lead to reductions in energy use, and result in savings associated with recovering and treating lower quantities of wastewater and treating and delivering lower quantities of water.
This guide focuses primarily on strategies for improving energy efficiency in water and wastewater facilities. Opportunities for improving energy efficiency in these facilities fall into three basic categories: 1) equipment upgrades, 2) operational modifications, and 3) modifications to facility buildings. Equipment upgrades focus on replacing items such as pumps and blowers with more efficient models. Operational modifications involve reducing the amount of energy required to perform specific functions, such as wastewater treatment. Operational modifications typically result in greater savings than equipment upgrades, and may not require capital investments (U.S. EPA, 2002). Modifications to buildings, such as installing energyefficient lighting, windows, and heating and cooling equipment, reduce the amount of energy consumed by facility buildings themselves.

Energy Efficiency in Water and Wastewater Facilities | Local Government Climate and Energy Strategy Series

1. Overview


Sources: California Energy Commission, 2005; U.S. EPA, 2010a; U.S. EPA, 2010b; Energy Center of Wisconsin, 2003

Treated Source

Water Treatment
100–16,000 kWh/MG

Water End Uses

0–14,000 kWh/MG

700–1,200 kWh/MG

Energy Opportunities • Use efficient pumping systems (pumps,
motors, variable frequency drives) • Capture energy from water moving
downhill • Store water ro avoid pumping
at times of peak energy cost
Treated Wastewater

Energy Opportunities • Install SCADA software • Use efficient pumping systems (pumps,
motors, variable frequency drives) • Install efficient disinfection equipment • Implement lighting,
HVAC improvements
e applications, ove
in approspteripast ab ay be useudse in the stewatetrhmre energy d wasome of Tarevaotieding

Waste water

Energy Opportunities
• Use efficient pumping systems (pumps, motors, variable frequency drives)
• Reduce distribution leaks • Implement automatic meter reading

Wastewater Collection & Treatment

Energy Opportunities • Use efficient pumping systems (pumps,
motors, variable frequency drives) • Capture energy from water moving downhill

Treated Wastewater Discharge

Energy Opportunities • Improve efficiency of aeration equipment
and anaerobic digestion
• Implement cogeneration and other onsite renewable power options (e.g., solar panels, wind turbines, low-head hydro)
• Implement lighting, HVAC improvements
• Fix leaks
• Install SCADA software
• Use efficient pumping systems (pumps, motors, variable frequency drives)
• Recycle water

Notes: • Energy intensity is given in kilowatt-hours (kWh) per million gallons (MG).
• The energy efficiency opportunities shown are examples, not an exhaustive list.
• The ranges in energy intensity shown here are for California, whose water and wastewater sectors have higher energy intensities overall than the rest of the United States. However, the energy intensity of most U.S. water and wastewater utilities will likely fall within these ranges (U.S. DOE, 2006).
• The ranges in energy intensity at each stage in the cycle are related to differences in factors such as the water source (deep aquifers being the most energy-intensive to pump); the volume of water transported; the distances and topography between sources, treatment plants, and end users; the quality of the source water; the intended end uses; and the technologies used to treat water and wastewater.
• The energy use associated with transport of wastewater from end users to wastewater treatment facility is included under “Wastewater Collection and Treatment.”
• For EPA’s latest guidelines on water reuse, please see http://www.waterreuseguidelines.org/.


1. Overview

Energy Efficiency in Water and Wastewater Facilities | Local Government Climate and Energy Strategy Series

Figure 1 shows typical ranges of energy use at each stage of the water use cycle, along with key opportunities for improving energy efficiency, conserving water, and using renewable energy. The processes of pumping and treatment are the largest consumers of energy in the water use cycle. In most cases, pumping is the largest source of energy use before, during, and after treatment of water. For wastewater, where energy-intensive technologies such as mechanical aerators, blowers, and diffusers are used to keep solids suspended and to provide oxygen for biological decomposition, treatment accounts for the largest share of energy use (California Energy Commission, 2005). Facility managers can perform energy audits or install monitoring devices that feed into their Supervisory Control and Data Acquisition (SCADA) system1 to learn where energy is being used in their facility and identify opportunities for energy efficiency improvements.
The most effective way for communities to improve energy efficiency in their water and wastewater facilities is to use a systematic, portfolio-wide approach that considers all of the facilities within their jurisdiction. This approach allows communities to prioritize resources, benchmark and track performance across all facilities, and establish cross-facility energy management strategies. A portfolio-wide approach not only results in larger total reductions in energy costs and GHG emissions, but enables communities to offset the upfront costs of more substantial energy efficiency projects with the savings from other projects. Adopting a portfolio-wide approach can also help local governments generate greater momentum for energy efficiency programs, which can lead to sustained implementation and continued savings.
Before developing a portfolio-wide approach, local governments first need to understand the steps involved in identifying and implementing energy efficiency improvements at individual facilities. This guide is designed to help local governments understand how to work with municipal or privately owned water and wastewater utilities to identify energy efficiency opportunities. It provides information on how water and wastewater utilities have planned and implemented programs to improve energy efficiency in existing facilities and operations, as well as in the siting and design of new facilities (see the text box on page 5). It also includes information on the benefits of energy
1 A SCADA system is a computer system used to monitor and control industrial, infrastructure, or facility-based processes.

efficiency improvements in water and wastewater facilities, expected investments and funding opportunities, and case studies. Additional examples and information resources are provided in Section 10, Additional Examples and Information Resources.
Since this guide provides information and examples for both the water and wastewater sectors, the icons below are used to help readers quickly identify examples and resources that focus specifically on one type of facility:
Water facilities
Wastewater facilities
Improving energy efficiency in water and wastewater facilities can produce a range of environmental, economic, and other benefits, including:
■■Reduce air pollution and GHG emissions. Improving energy efficiency in water and wastewater facilities can help reduce GHG emissions and criteria air pollutants by decreasing consumption of fossil fuel-based energy. Fossil fuel combustion for electricity generation accounts for approximately 40 percent of the nation’s emissions of carbon dioxide (CO2), a principal GHG. It also accounts for 67 percent and 23 percent of the nation’s sulfur dioxide (SO2) and nitrogen oxide (NOx) emissions, respectively. These pollutants can lead to smog, acid rain, and airborne particulate matter that can cause respiratory problems for many people (U.S. EPA, 2011a; U.S. EPA, 2011b).2
2 According to EPA, energy use in commercial and industrial facilities accounts for nearly 50 percent of all U.S. GHG emissions (U.S. EPA, 2011a).

Energy Efficiency in Water and Wastewater Facilities | Local Government Climate and Energy Strategy Series

2. Benefits


The Green Bay, Wisconsin Metropolitan Sewerage District has two treatment plants that together serve more than 217,000 residents. One of the treatment plants installed new energy-efficient blowers in its first-stage aeration system, reducing electricity consumption by 50 percent and saving 2,144,000 kWh/year— enough energy to power 126 homes—and avoiding nearly 1,480 metric tons of CO2 equivalent,3 roughly the amount emitted annually by 290 cars (U.S. EPA, 2010a; U.S. EPA, 2011d; U.S. EPA, 2011f).
Wastewater facilities with an anaerobic digester can use biogas generated by the digester to produce heat, and in many cases electricity as well. As a rule of thumb, each million gallons per day of wastewater flow can generate enough biogas in an anaerobic digester to produce 26 kilowatts of electric capacity and 2.4 million Btu per day of thermal energy in a CHP system (U.S. EPA, 2011g).
Not all wastewater facilities use anaerobic digesters, so CHP is not an option for all wastewater plants. Furthermore, some facilities with anaerobic digesters must rely on supplemental sources to provide enough energy for electricity generation in their CHP system.
For more information on CHP in wastewater facilities, see http://www.epa.gov/chp/documents/wwtf_ opportunities.pdf.
■ Reduce energy costs. Local governments can achieve significant cost savings by increasing the efficiency of the pumps and aeration equipment at a water or wastewater treatment plant. A 10 percent reduction in the energy use of U.S. drinking water and wastewater systems would collectively save approximately $400 million and 5 billion kWh annually (U.S. EPA, 2011g). Facilities can also use other approaches to reduce energy costs, such as shifting energy use away from peak demand times to times when electricity is cheaper or (for wastewater plants) using CHP systems to generate their own electricity and heat from biogas.
3 Carbon dioxide equivalent is a measure used to compare the emissions from different GHGs based on their respective global warming potential (GWP). Carbon dioxide equivalents are commonly expressed as metric tons of carbon dioxide equivalent (MTCO2e). The carbon dioxide equivalent for a gas is derived by multiplying the tons of the gas by the associated GWP. In other words, MTCO2e = (metric tons of a gas) * (GWP of the gas).

With more than two-thirds of the up-front installation and maintenance costs covered by the State of Minnesota and a local utility, the Albert Lea Waste Water Treatment Plant in Albert Lea, Minnesota developed a 120-kW mictroturbine CHP system, which saves the plant about $100,000 in annual energy costs. About 70 percent of the savings resulted from reduced electricity and fuel purchases, and the remainder from reduced maintenance costs. The installation of the CHP system raised awareness at the plant about energy use in general, and led to a number of other energy efficiency improvements and additional cost savings (U.S. EPA, 2011f).
■■Support economic growth through job creation and market development. Investing in energy efficiency can stimulate the local economy and spur development of energy efficiency service markets. The energy efficiency services sector accounted for an estimated 830,000 jobs in 2010, and the number of jobs was growing by 3 percent annually (ACEEE, 2012). Most of these jobs are performed locally by workers from relatively small local companies because they typically involve installation or maintenance of equipment (ACEEE, 2012; Lawrence Berkeley Laboratory, 2010). Furthermore, facilities that reduce their energy costs through efficiency upgrades can spend those savings elsewhere, often contributing to the local economy (Lawrence Berkeley Laboratory, 2010).
■■Demonstrate leadership. Investing in energy efficiency epitomizes responsible government stewardship of tax dollars and sets an example for others to follow. By implementing energy efficiency and water efficiency projects at water and wastewater facilities, a local government can demonstrate not only the dollars saved, but the environmental co-benefits that are obtained from reducing energy and water use. Installing energy-efficient products (e.g., more efficient pumps), water-efficient products (e.g., WaterSense products), and renewable energy technologies (e.g., solar panels) may facilitate broader adoption of these technologies and strategies by the private sector— particularly when communities publicize the economic and environmental benefits of their actions.


2. Benefits

Energy Efficiency in Water and Wastewater Facilities | Local Government Climate and Energy Strategy Series
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